Fix installation with OVN backend and compilation

This patch fixes several issues related to the installation with
OVN backend with the OVS/OVN compilation enabled.

The OVS/OVN local directories prefix, when both services are compiled,
is now "/usr/local".

The "ovn_agent._run_process" function is calling "ovs-appctl" to
configure the logging settings of several services. Instead of
using the service name, the ctl socket file is used instead. That
is more robust and does not fail in systems with previous
installations.

Closes-Bug: #1960514

Change-Id: I69de5333393957593db6e05495f0c3c758efefdf
diff --git a/lib/neutron_plugins/ovs_base b/lib/neutron_plugins/ovs_base
index 8acf586..cc41a8c 100644
--- a/lib/neutron_plugins/ovs_base
+++ b/lib/neutron_plugins/ovs_base
@@ -68,7 +68,7 @@
 function _neutron_ovs_base_install_agent_packages {
     if [ "$Q_BUILD_OVS_FROM_GIT" == "True" ]; then
         remove_ovs_packages
-        compile_ovs False /usr /var
+        compile_ovs False /usr/local /var
         load_conntrack_gre_module
         start_new_ovs
     else